* @param handler the handler to disable.
* @param handlerName the handler name to disable.
*/
static void disableHandler(final Handler handler, final String handlerName) {
if (handler instanceof ExtHandler) {
final ExtHandler extHandler = (ExtHandler) handler;
extHandler.setEnabled(false);
} else {
Map<String, Filter> disableHandlers = ROOT.getAttachment(DISABLED_HANDLERS_KEY);
if (disableHandlers == null) {
disableHandlers = new HashMap<String, Filter>();
final Map<String, Filter> current = ROOT.attachIfAbsent(DISABLED_HANDLERS_KEY, disableHandlers);